bgp configuration.

[tushar47]

Dear sir,

I am working in Class A ISP, running BGP with my service provider. I have 2 links with the same service provider.

1st link : 2 Mbps 1:1

2nd link : 2 Mbps 1:4

Please tell me that how can i configure that all local traffic comes through 2nd link and all international traffic comes through 1st link.

2Mbps 1:4 means 512 k capping is for international traffic and rest if for local trafic.

Please guide me.

Regards,

Ashu.

[Georg Pauwen]

Hello Ashu,

it depends on what you define as local and international traffic. Is that based on Ip addressing, AS paths, or communities ? Can you elaborate on what the decision should be based on ?

Regards,

GP

[sdoremus33]

As the last post stated what are you varying these routes on... anyway you simply can create bgp map classes and append each class to the interface you want the traffic to traverse through

[tushar47]

Dear sir,

Local traffic means traffic within my country.

International means the traffic outside my country.

Regards,

Ashu.

[Danilo Dy]

lol

This LOCAL and INTERNATIONAL is created by major ISP's in some countries. The charges for LOCAL and INTERNATIONAL bandwidth is different (high cost for INTERNATIONAL of course).

But don't be fool with the LOCAL and INTERNATIONAL word, they are not what they seems to be. I don't think major ISP's can determine all IP Address in your country or even in your location where there are multiple ISP's, some MNC even bought their own prefix and AS. Some MNC may bought their prefixes and AS from North America but they may have global offices interconnected together in a WAN, they may have link some offices in major cities in the world to ISP's in that area advertising only few prefixes per ISP. Besides, what if other ISP and/or MNC change their prefix and AS? Who will monitor it to update the LOCAL and INTERNATIONAL prefixes your ISP is advertising to you?

In my observation they separate them this way;

- Major ISP have tons of ip prefixes > they tag it as LOCAL > They are assigning their prefixes to their customers (MNC's, ADSL, Internet Subscribers, etc...)

- Other prefixes not belong to them > they tag it as INTERNATIONAL > NOTE: Some ISP change the name from INTERNATIONAL to INTERNET, because INTERNATIONAL is confusing, most people think the ip address is out of their country.

Then;

- They advertised their LOCAL prefixes with lower MED to your 2Mbps and advertised their INTERNATIONAL/INTERNET prefixes with higher MED to your 2Mbps

- They will advertised their INTERNATIONAL/INTERNET prefixes with lower MED to your 512Kbps and advertised their LOCAL prefixes with higher MED to your 512Kbps

Doing it this way, they will have attractive packages for their subscribers.

Since your 2Mbps is cheaper than your 512Kbps, use Weight or Local-Preference to use your 2Mbps as primary (best path) for all your outgoing traffic. This way you can save BW and money :)

Monitor your bw usage (using Cricket or MRTG) and adjust your outgoing and incoming using MED (incoming), Weight and Local-Preference (Outgoing). I'm not to sure if you can adjust your incoming, since your ISP is separating LOCAL and INTERNATIONAL/INTERNET they may have some configuration that will always override your MED for your incoming traffic :)